1. Field of the Invention
The present invention relates to an apparatus which learns a recognition dictionary, and a method which learns the recognition dictionary.
2. Description of the Related Art
Conventionally, as a method of detecting an object from an image, there is known a method which is disclosed in Viola and Jones “Rapid Object Detection using Boosted Cascade of Simple Features”, Computer Vision and Pattern Recognition, 2001 (hereinafter, called a non-patent document). Further, in such a case of learning a matching dictionary, there is known a method which is disclosed in Japanese Patent Application Laid-Open No. 2008-287378.
It is required to reduce the number of subject images necessary in case of learning the matching dictionary, or to improve performance on the condition of the same number of subject images. Japanese Patent Application Laid-Open No. 2008-287378 discloses a technique of generating a duplicate subject image from a certain subject image by performing mirror reversal and micro-rotation to the subject image. However, in this technique, a duplicate subject image is not generated for an image which is not mirror image symmetrical, whereby it is impossible to reduce the necessary number of the subject images.